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Nickel boron (NiB) coatings were deposited onto copper using a nickelglycine (Ni-Gly) plating solution and morpholine borane (MB) as a reducing agent. It has been determined that using MB as a reducing agent in the Ni-Gly plating solution produces NiB coatings, which exhibit typical cauliflower-like textures. The deposition rate of the NiB coatings and their composition depend on the concentrations of the reducing agent (MB) and the ligand (Gly), in addition to the pH and temperature of the plating solution. The highest deposition rate (3.42 mg cm–2 h–1) of the NiB coating was obtained when the plating bath was operated at pH 5 and 60°C temperature. Using this method, NiB coatings containing 10–20 at.% of boron can be obtained.

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In this study the graphene supported PtCo catalyst with the Pt:Co molar ratio equal to 1:7 was fabricated by means of the rapid microwave heating method with the aim to use it in an alkaline fuel cells, using ethanol, methanol and borohydride as fuel. It was found that the PtCo/GR catalyst with an average particle size of ca. 1-3 nm was synthesized by means of microwave heating of Pt(IV) and Co(II) salts in ethylene glycol solutions. The PtCo/GR catalyst shows an enhanced activity towards the oxidation of H2 generated by catalytic hydrolysis of BH4 – and direct oxidation of BH4 – ions as well as methanol and ethanol oxidation as compared with that at the graphene supported bare Co and Pt/C catalysts. It should be noted that the electrocatalytic activity of the PtCo/GR catalyst depends on the type of fuel.

In the present study the activity of the Co with a fiber structure decorated by Pt or Au nanoparticles (denoted as Pt/Cofiber and Au/Cofiber) was investigated towards the electro-oxidation of hydrazine. At first, Co coating with a fiber structure and the thickness of ~3 µm was electroplated onto the Cu surface. Then, the Pt nanoparticles were deposited on the prepared Cofiber/Cu by its immersion into the 1 mM H2PtCl6 + 0.1 M HCl solution at the temperature of 25 oC for 10-60 s, respectively, whereas Au nanoparticles were deposited on Cofiber/Cu by its immersion into the 1mM HAuCl4 + 0.1 M HCl for 10-300 s. Field Emission Scanning Electron Microscopy, Energy Dispersive X-ray Spectroscopy and Inductively Coupled Plasma Optical Emission Spectroscopy were used for determination of morphology, structure and composition of the prepared catalysts. The electrocatalytic properties of catalysts were evaluated with respect to the electro-oxidation of hydrazine in an alkaline medium by means of cyclic voltammetry and chrono-techniques. It was found that the Pt loadings were 5, 15 and 29 µg cm–2 in the prepared Pt(Cofiber)/Cu catalysts after the immersion of Cofiber/Cu into the platinum-containing solution for 10, 30 and 60 s, respectively. The Au loadings were 20, 28 and 96 µg cm–2 in the prepared Au(Cofiber)/Cu catalysts after the immersion of Cofiber/Cu into the gold-containing solution for 10, 60 and 300 s, respectively. The cobalt with a fiber structure decorated with the Pt or Au nanoparticles show enhanced electrocatalytic activity towards the electro-oxidation of hydrazine in an alkaline medium as compared to that of bare Co deposited on the Cu surface.   Acknowledgment  This research was funded by a Grant (No. TEC-06/2015) from the Research Council of Lithuania.